1. Field of the invention
The present invention relates to a continuous type centrifugal separator, and more particularly to a continuous type centrifuge for washing the blood of the patient having blood disorders.
2. Related Background Art
In case of blood disorders such as jaundice, for example, it is observed that plasma is contaminated and the blood washing process is usually carried out for the treatment of the jaundice by way of continuously removing the blood from the doner patient, centrifugally separating the contaminated plasma to be abandoned, and returning red blood cells with addition of plasma preparations to the body of the patient under conditions flow process. Also, this washing process is being used for the treatment of various blood disorders resulting from abnormalities within the plasma, in such cases as malignant peraprotenemias and hypercholesterolemia.
For a continuous type centrifugal separator which can be used for the blood washing process as above mentioned, it is required that a closed system is kept in a flow process between the blood vessel of the patient and a centrifugal case via a circulation channel of the tubes for the whole blood and the separated blood components. Otherwise, bacteria contamination may possibly occur to cause hazards to the health of the patient. Therefore the most essential requirement for this type of a continuous centrifugal separator consists in an arrangement to ensure the completely closed system for the blood tubes.
Such a centrifugal liquid processor is disclosed in Japanese Patent Application Laid open No. 120470/1976 (corresponding to U.S. Ser. Nos. 562,748, abandoned, and 657,187, now Pat No. 4,113,173). In this prior art, a centrifugal case is positively rotated at the speed twice as high as an engaging member of blood tube, which is disposed on the position debiated from the rotational axis of the centrifugal case in the same direction thereof and the ratio of the speed of the case to that of the tubes is set to be 1/2 to eliminate any possible twisting of the blood tubes, thereby realizing the completely closed system in the continuous type centrifuge without using a rotary coupling for the connection between the centrifugal case and the blood tubes. However, the prior art is accompanied with such drawbacks that a driving mechanism for rotating the engaging member is so highly complicated that it is difficult to keep the rotation balance in case of high speed rotation, and the component parts of the apparatus may often be destroyed due to vibration.